Bucket ejector assembly for an excavating grab



Jlm 2. 1 I G. L. GU-[NOT 3,451,151

7 BUCKET EJECTOR ASSEMBLY FOR AN EXCAVATING GRAB Filed Oct. 51, 1967 INVENTOZ GABRIEL L. Gumc'r United States Patent 3,451,151 BUCKET EJE'CTOR ASSEMBLY FOR AN EXCAVATING GRAB Gabriel L. Guinot, Le Plessis-Belleville, France, assignor to Societe Anonyme Poclain, Le Plessis-Belleville, Oise,

France, a French society Filed Oct. 31, 1967, Ser. No. 679,491 Claims priority, application France, Nov. 7, 1966,

82,773 Int. Cl. B66c 3/02; E2111 31/04, 33/132 U.S. Cl. 37-187 2 Claims ABSTRACT OF THE DISCLOSURE This invention relates to a bucket assembly for a mechanical excavator or other earth Working machine and is concerned with a bucket assembly of the type in which the bucket, sometimes called a grab, comprises two bucket halves or shells pivotally mounted on a socalled spreader attached to the fixed member of a ram, usually a doubleacting hydraulic ram, and connected by connecting rods or arms to the movable member of the ram.

In some circumstances, for example when operating in heavy soils, it sometimes happens that the excavated soil adheres to the walls of the bucket and does not drop out of the bucket when the two halves or shells are pivoted into the open position of the bucket.

The object of the present invention is to overcome this disadvantage and this is achieved, according to the invention, by providing each of the bucket halves or shells with an ejector device which operates to eject the contents of the bucket automatically as the bucket halves or shells are pivoted into the open position of the bucket.

According to the invention the bucket assembly comprises two bucket shells each pivotally connected to the fixed member of a ram and each having an ejector pivotally mounted therein, each bucket shell and its ejector being pivotable about a common axis, each bucket shell being connected with the movable member of said ram by a first connecting rod or arm pivotally attached both to a bucket shell and said movable member and each of said ejectors being connected with said movable member of the ram by a second connecting rod or arm pivotally attached both to said movable member and an ejector, the distance between said common axis and the axis about which each of said second connecting rods or arms are pivoted to an ejector being greater than the distance between said common axis and the axis about which a first connecting rod or arm is pivoted to said bucket shell.

In order that the invention may be more clearly understood one particular embodiment thereof will now be described, by way of example, with reference to the accompanying drawing which is a part sectional side elevation of a bucket assembly according to the invention showing one bucket half or shell in the partly open and one in the closed position of the bucket.

Referring to this drawing the bucket assembly comprises a support member 1 coupled at one end to the jib of a mechanical excavator or other earth working machine and carrying at its other end a so-called spreader 2 to which two bucket shells 3 and 4 are pivoted about pivots 5 and 5a, respectively. Each of said bucket shells is connected by a first connecting rod or arm 6, 7 to the movable member 12. of a ram, preferably a double-acting hydraulic ram, of which the movable member 12 constitutes the cylinder of the ram in which is slidable a piston (not shown), formed as an integral part of the support member 1 constituting the fixed part of the ram. The first connecting rod or arm 6, 7 of each bucket shell 3, 4 is pivotally connected at one of its ends to the bucket shell 3, 4 by a pivot 8, 9 and pivotally connected at its other end to the movable member of the ram at 10, 11.

In accordance with the present invention each bucket shell 3, 4 has pivotally mounted therein an ejector 13, 14 in the form of an ejector plate having an area corresponding substantially to the internal cross-sectional area of the bucket shell. The ejector plate 13, 14 is pivotally mounted on the pivot 5, 5a on which the bucket shell is pivoted. Thus the ejector and the bucket shell are pivotable about a common axis. Each of said ejectors 13, 14 is connected to the movable member 12 of the ram by a second connecting rod or arm 15, 16. Said connecting rod or arm is pivotally connected at one of its ends to the ejector plate at 17, 18 on the side of the ejector plate opposite to its pivot axis 5, 5a and is pivotally connected at 19, 20 to the first connecting rod or arm 6, 7 in the neighborhood of the pivot axis 10, 11 of the first connecting rod 6, 7 and is thus connected to the movable member of the ram at 19, 20.

As will be apparent from the drawing the distance between the common pivot axis 5, 5a and the axis 17, 18 about which the second connecting rod or arm 15, 16 is pivoted to the ejector 13, 14 is greater than the distance between said common pivot axis 5, 5a and the axis 8, 9 about which thefirst connecting rod or arm 6, 7 is pivoted to the bucket shell 3, 4.

With this arrangement the ejector 13, 14 will be positioned substantially at the level of the upper edge of the bucket shell, as shown on the right hand side of the drawing, when the bucket is in the open position and thus does not materially limit the capacity of the bucket shell. When the bucket is in the open position, the ejector will be moved to the position indicated in broken lines, as shown on the left hand side of the drawing. Thus it will be understood that during the pivoting of the bucket shells to open the bucket the ejector will operate automatically to simultaneously eject the contents of the bucket and scrape the walls thereof.

By suitably choosing the length of the connecting rod or arm 15, 16; the distance between the pivot axes 5, 17 and 5a, 18; and the dimensions of the ejector; the distance of travel of the ejector can be adjusted such that it can move into its extreme ejecting position without risk of it being jammed by stones or other solid bodies and without reducing the volume of the bucket.

The connecting rods 15, 16 could be connected directly to the movable member 12 of the hydraulic ram instead of indirectly through the connecting rods or arm 6, 7.

I claim:

1. A bucket assembly for a mechanical earth working machine, comprising two bucket shells each pivotally connected to the fixed member of a ram and each having an ejector pivotally mounted therein, each bucket shell and its ejector being pivotable about a common axis, each bucket shell being connected with the movable member of said ram by a first connecting arm pivotally attached both to a respective bucket shell and said movable member and each of said ejectors being connected with said movable member of the ram by a second connecting arm pivotally attached both to said movable member and a respective ejector, the distance between said common axis and an axis about which each of said second connecting rods are pivotally mounted to an ejector being greater than the distance between said common axis and the axis about which a first connecting arm is pivotally connected to the respective bucket shell.

2. A bucket assembly for a mechanical earth working machine, according to claim 1, wherein each of said sec ond connecting arms are pivotally connected to a respective first connecting arm in the neighborhood of the pivotal axis at which each of said first connecting arms 4 are pivotally connected to the movable member of the ram.

References Cited UNITED STATES PATENTS 2,828,038 3/1958 DorkinS. 3,314,709 4/1967 Guinot.

FOREIGN PATENTS 160,858 10/ 1957 Sweden. 1,166,432 3/1964 Germany.

ROBERT E. PULFREY, Primary Examiner.

CLIFFORD D. CROWDER, Assistant Examiner.

US. Cl. X.R. 

